WASHINGTON — President Trump said Thursday he will withhold publication of some documents related to the assassination of President John F. Kennedy because of national security concerns.

"I agree with the Archivist's recommendation that the continued withholdings are necessary to protect against identifiable harm to national security, law enforcement, or foreign affairs that is of such gravity that it outweighs the public interest in immediate disclosure," Trump said in a memorandum.

The decision is likely to irk historians who say the government secrecy is contributing to conspiracies surrounding Kennedy's murder.

At the same time, Trump did authorize the release of more than 19,000 other documents.

“The cover up continues," author Jefferson Morley, a longtime JFK assassination researcher and author who led a years-long lawsuit against the CIA seeking the documents.

"What can you say?" Morley added. "The clear intent of congress was that all of this material would be in the public record with a few possible exceptions. It’s appalling. It’s very disappointed. So then the question is, what are they hiding?”